Ch 3 Developmental Theories & Aging

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Molecular/Cellular Theories of Aging: ROS (Oxidation)

(Oxidation) - One of the most popular theories of aging is the free radical theory - Free radical or reactive oxygen species (ROS) are molecules that are generated during the oxidation process in cells; they have an unpaired electron which make them unstable and extremely chemically reactive - Four lines of evidence that support the ROS theory of aging: 1) longer lived species' mitochondria produce few free radicals 2) increasing levels of lipofuscin (cellular waste products) with age 3) the correlation between oxidation levels and deletions in mtDNA 4) muscles with sarcopenia (atrophy) have mitochondria with lots of mtDNA damage - Lines of evidence that do not support the ROS theory of aging: 1) "Knockout" mice (those who are genetically altered to delete a gene) with mtDNA mutations and deletions do show accelerated age-related illnesses such as sarcopenia, osteoporosis, and alopecia (hair loss) but they do not necessarily show more evidence of increased ROS 2) Damaged/age muscle cells may emit fewer ROS as they may be processing less oxygen

Lipofuscin: Molecular/Cellular Theories of Aging (biological theories)

- Aging cells also accumulate waste matter called lipofuscin, a dark mixture of lipoproteins and various waste products. Normally, these waste products are disposed of via liposomal enzymes, but this process is impaired in older cells (for as yet unknown reasons). - Lipofuscin is found in nearly all cell types, from heart muscle cells to neurons, and increases with age. - Early studies failed to document an association between the presence of lipofuscin and cell functioning; more recent findings, however, suggest that there may be different types of lipofuscin, one of which may be associated with Alzheimer's disease > Furthermore, in rats, the presence of lipofuscin in neurons may affect their functioning (Sharma & Singh, 1996), and when lipofuscin production is artificially induced in human cells in vitro, it blocks cell proliferation and induces cell death - Too much lipofuscin can also interfere with autophagy, a process by which damaged cells dismantle themselves and recycle needed nutrients - Accumulation of lipofuscin may be a biomarker for metabolic rate, because it reflects oxidation and thus the production of free radicals > Furthermore, severe caloric restriction in rats appears to decrease the rate of production of lipofuscin

changes in the temporal organization of physiological rhythm (Homeostasis and Balance Theories): System-Level Theories (biological theories)

- Aging is also associated with changes in the temporal organization of physiological rhythm. > Ex. there is a reduction in the circadian amplitude of processes such as sleep, plasma cortisol, body temperature, and a variety of neuroendocrine hormones > for example, body temperatures fluctuate over a 24-hour period, with the lowest temperatures occurring in the early hours of the morning for individuals with typical circadian rhythms. > In older adults, however, these lower temperature and coinciding sleep phases may occur 1 to 2 hours earlier, and elders may have difficulty adjusting to changes in time zones. - For reasons that are as yet unclear, physiological rhythms also become less complex with age, showing decreased variability. > The consequences of this are as yet unclear but there is increasing evidence that dysregulation in circadian and other physiological rhythms are associated with problems of the oxidative stress response and DNA repair mechanisms and so might prove to be crucial mechanisms for aging

Current Theories: Goal-Oriented Models

- Baltes (1987) characterized development in adulthood as a balance between gains and losses with relatively more gains in early adulthood and more losses later * did not propose a series of stages but instead argued for a process approach that describes adaptation to aging - Successful aging is characterized by selection, optimization, and compensation (SOC) * pianist Arthur Rubenstein is a classic example of the SOC process - Brandstädter's (1999) self-development model emphasizes goals but argues that there are developmental changes in goals from young adulthood to late life - More recently, Brandstädter, Rothermund, Krantz, and Kühn (2010) argued that ego-transcendent goals take precedence toward the end of life

Ontogenetic Models: Psychosocial Theories of Aging

- Classical ontogenetic models posit that development stems from internal forces and consists of stages that are universal, sequential, and irreversible * universal means applicable to everyone regardless of gender, social status, or culture * the stages are sequential, follow a definite order, and are thought to be irreversible (they represent achievements) - Psychodynamic schools focused largely on personality and development: * Erikson (1950) modified Freud's psychosexual theory of early childhood to a psychosocial model that extended from birth through late life > posited eight stages ranging from basic trust versus mistrust in early infancy, to ego integrity versus despair in late life > thought to satisfy all the requirements of a purely ontogenetic theory * Peck (1968) and Vaillant (1977) elaborated in various ways on Erikson's basic paradigm * Jung (1933) focused on adult development believing that adolescents develop a persona: a false self developed to conform to adult social role conventions * Bühler emphasized meaning and goals in development rather than strict ontogenetic stages - Psychological adult development and aging theorists emphasized internal processes and posited that development had a goal, or telos. That goal was variously described but usually involved psychological integration, autonomy, and /or the development of choice in adulthood

DNA in mitochondria (oxidation): Stochastic Processes (genetic theories)

- DNA in mitochondria may be particularly susceptible to damage (Quinlan, Treberg, & Brand, 2011). - The oxidation process is carried out in the mitochondria. - The close proximity of mitochondrial DNA (mtDNA) to reactive oxygen is part of the reason why they are susceptible to damage. - mtDNA repair mechanisms also appear to be less efficient. - Cells in highly oxidative organs (such as the heart, brain, and skeletal muscles) have the most damaged mtDNA in later life. - If a cell's energy source is damaged, then the functioning of the whole cell is impaired, and it becomes a candidate for apoptosis. - Thus, damaged mtDNA may be a cause of significant cell loss in late life. > However, it may be possible to dismantle and recycle mitochondria, a process called autophagy, which is thought to be a powerful antiaging process

DST and systems theory

- DST expands on this approach and focuses not only on bidirectional feedback loops but also on such phenomena as emergent properties, which cannot be reduced to their elemental components but are new phenomena that reflect the transaction among various components. - They also focus on cross-system transactions and have developed new methodologies to examine this, including system dynamics, agent- based modeling, and network analysis (see Urban et al., 2011 for further explication of these methodologies).

DST

- DST has very similar assumptions to developmental systems but, if anything, draws more heavily on general systems theory. - Von Bertalanffy's (1969) classic systems theory model holds that most systems have deviation-countering mechanisms to maintain homeostasis. > In other words, if change occurs, mechanisms typically exist for countering that change and returning the organism to a steady state. > Classic examples include blood pressure regulation, heart rate, respiratory rate, glucose reg- ulation, and DNA repair. - Maruyama (1963) argued that systems can and do change over time. > Once a system is jarred out of homeostasis, then deviation amplification mechanisms can take over, accelerating the change or imbalance. > Our contention, however, is that Maruyama's deviation amplification model may be a better framework for integrating theories of aging, because it includes mechanisms for maintaining homeostasis as well as for promoting change, both positive and negative.

Current Theories: Life Course Theory

- Development is seen as a series of transitions and choice points that are influenced both by the immediate social context and the larger sociohistorical period as well as gender and social roles - Elder and Shanahan (2006) and Dannefer and Settersten (2010) have developed a much more elaborate theory of life course development, which examines the ways in which cohort and historical periods affect the life course structure of individuals * Elder and Shanahan (2006) argued for an independent life course - Elder (1974) conducted a classic study of the effects of the Great Depression on subsequent development using archives from what is now known as the Intergenerational Study - Settersten and Hagestad (2015) argue that subjective aging is largely intersubjective: the experience of aging is dependent upon shared meanings developed over a life span through socialization processes

classic vs. current theories: Interrelationships Among Theories

- Early theories of adult development tended to focus on one aspect of adult development (e.g., personality or social), whereas contemporary theories tend to emphasize multiple influences. - Many of these theories focus more on describing the older population and/or the importance of the social context rather than on developmental processes per se and thus may not be seen as relevant to biological processes. - Furthermore, it is interesting that the current models may describe changes in personality and adaptation from young adulthood to midlife. > For example, P. B. Baltes (2002) reported that SOC peaks in midlife, while Labouvie-Vief (2002) found that cognitive and emotional complexity also peak in midlife. > Thus, we may know less about the process of development in late life. - Most current theories emphasize some sort of agency, or conscious choice, in developmental processes. - Some theories posit the opportunity for conscious choice as an outcome of developmental processes. - Although biological theories seldom address choice and agency, relying primarily on causal physiological models, health psychology often addresses the impact of lifestyle choices on health and the development of disease. > These choices, which are addressed in the third section of this volume, may accelerate or decelerate the aging process. - These theories also may play an important role in how people adapt to biological changes with age, and thus they have relevance for quality of life in late life. - Finally, there has been a growing interest in resilience in late life—that is, how older adults manage to maintain their emotional equilibrium and quality of life in the face of the physical and psychosocial losses endemic in late life. - While these theories are new, they build on a wealth of research that focuses on how individuals can successfully cope with stress and help to explain why older adults often report being happier, less lonely, and relatively healthy despite the existence of chronic illness and the loss of loved ones. - Given that older adults are survivors, how they develop resilience is central to understanding optimal aging.

Interrelationships Among Theories

- Early theories of adult development tended to focus on one aspect of adult development, whereas contemporary theories tend to emphasize multiple influences - Most current theories emphasize some sort of agency, or conscious choice, in developmental process - Biological theories seldom address choice and agency, relying primarily on causal physiological models - Health psychology often addresses the impact of lifestyle choices on health and the development of disease - Growing interest in the resilience in late life—how older adults manage to maintain their emotional equilibrium and quality of life in the face of the physical and psychosocial losses endemic in late life

psychosocial theories of aging fig 3.2: p 48

- Figure 3.2 presents a flowchart of the intellectual history of the major theories of adult development. - It is not meant to be inclusive but rather illustrative, tracing the origins of the major schools and their development from classic to modern theories. - Further, it loosely groups theorists into schools of influence by cohort and is not meant to indicate intellectual lineage (e.g., Baltes did not study with Erikson). - Thus, Baltes, strictly speaking, is not a psychodynamicist. > However, one could argue that the life span approach grew out of the ego development approach, in that the latter presaged the notion of individual development across the life span. - Further, developmental theories are replete with influences that cut across schools, but unfortunately there was insufficient space to show the cross-linkages. > Piaget, for example, was also influenced by Gestalt psychology, but self-identified as a structuralist. - Labouvie- Vief's theory is on post-formal operations, and thus is Piagetian in origin, but clearly has psychodynamic influences as well. The figure is used simply as a heuristic to organize this discussion.

transactionalism

- For the past 200 years, science has been guided very successfully by reductionism, which seeks to break complex phenomena into its component parts and examine causal processes - However, the complexities of scientific phenomena gave rise to an interactionist perspective in which phenomena were seen as arising from the joint action or interaction between two factors, which were nonetheless seen as causal. > Ex: the famous equation B = f (P E) was Lewin's attempt to demonstrate that behavior is a function of both personal and environmental factors. > this assumes that the causal factors are independent. - This interactionist framework is yielding to a transactional one, in which it is understood that phenomena are influenced by multiple factors that are not only influencing the target phenomenon but also influencing each other. -This has been variously called relational interaction, coaction, reciprocal bidirectionally, or multidirectionality - This perspective has given rise to developmental systems theory (DST; Lerner, 2006) and its more methodological counterpart, dynamic systems theory (DYST; Urban, Osgood, & Mabry, 2011).

Genetic theories

- Genetic theories are seen primarily as aging acceleration theories. - Recall that aging accelerating genes means that such theories are trying to understand how some variables (such as genes or properties of genes) are responsible for promoting or hastening the aging process. - In theories and research in mammals, such as humans, theories have taken several different forms. - The first biological theories were pretty "crude" ideas in which informal theories that have been around for centuries were popular. - With the discovery of DNA and its influence on cell life, we started to get theories based on genes. - The Hayflick Limit was the first dominant idea. He published research suggesting that certain mammalian cells dies out after a certain number of replications. > This idea is still around but has been pushed to include discussions of telomeres which are parts of the DNA strands that are important to cell division/replication. - There is a whole industry of nutritional supplements designed to have a positive effect on telomeres. > Those supplements would be age decelerators. > The evidence that any of them work is sketchy at best, down right fraudulent in others. - The tricky part of this is something called stochastic processes. > This refers to the accumulation of errors in DNA across many replications. > So you end up with kidneys that have lots of cells with DNA errors and therefore kidney function declines. > The accumulation of errors may be influenced by nutrition, drugs, alcohol, and stress. - Don't worry about the specifics of DNA repair, just understand the basic idea that DNA can "repair" itself or the body can kill off cells that simply have too many errors. - Caloric restriction has received a lot of press, based on a small number of human studies and lots of studies of mice. > To work, caloric restriction needs to start early, be pretty severe, and continue through adulthood and old age.

Current Theories: Resilience and Aging

- Has recently emerged as a "hot topic" in the field of adult development and aging - Resilience, as defined by Allen, Haley, Harris, Fowler, and Pruthi (2011), is "the developmental process of being mindful of and prioritizing those behaviors, thoughts, and feelings that facilitate contentment within a specific developmental, physical, emotional, and spiritual, context" - Resilience, as defined by the WHO (2002), is "the process of optimizing opportunities for health, participation, and security in order to enhance quality of life as people age" - Resilient individuals are those who are more likely to maintain orthogonality of positive and negative affect under stress - Charles (2010), Charles & Hong (2016), and Aldwin, Park, and Spiro (2007) noted an interesting conundrum in the aging literature, namely older adults are physiologically more vulnerable to stress and respond more adversely to stressful stimuli in laboratory settings, but, in field studies, they often show less vulnerability to stress > All posited that older adults appear to be better at regulation emotions, especially in interpersonal settings > Differ in that Charles focused on the impact of time perception, whereas Aldwin et al. focused on appraisal

Life Course Theory: (current theories)

- In life course theory, development is seen as a series of transitions and choice points that are influenced both by the immediate social context and the larger sociohistorical period as well as gender and social roles (Moen, 1992). - Current theorists such as Elder and Shanahan (2006) and Settersten (2009) have developed a much more elaborate theory of life course development, which examines the ways in which cohort and historical periods affect the life course structure of individuals. > For example, Elder (1974) conducted a classic study of the effects of the Great Depression on subsequent development using archives from what is now known as the Intergenerational Study, which followed children born in the 1920s and 1930s through their childhood and adulthood into late life. > Elder showed that the Depression influenced the life course of individuals, but how it did so was modified by social class and family resources. > Not everyone was equally affected by the Depression, and there was an interaction between economic deprivation and social class. > Children from working-class families that were economically deprived generally had very difficult, chaotic lives. > They were less likely to finish high school than their nondeprived peers and consequently had poorer work histories, less savings, troubled marital histories, and worse relationships with their children. > Curiously, though, the middle-class children who were economically deprived did better than their nondeprived peers: They were more likely to achieve higher education and had better jobs and finances, more stable marriages, and better relations with their children. > The stress of economic deprivation apparently motivated them to focus and achieve more in their lives. - Thus, Elder and Shanahan (2006) argued for an interdependent life course: How individuals weather transitions, turning points, and hard times is a function of personal choices and those of others in the immediate social context, the availability or lack of resources, and larger historical events.

chaos theory & the environmental stress

- In many ways, Maruyama's (1963) theory represents an early precursor to chaos theory, which is a wonderful way of specifying nondeterminate processes—those that do not follow simple cause-and-effect processes. - Nondeterminate processes occur when systems have a large number of interacting variables (e.g., weather systems). - Chaos theory shows how initially small changes can result in very large differences among systems or individuals. - It has been used to describe cascade effects in cardiovascular functioning problems and has been proposed as a general model for aging (Goldberger, 1996). - Aldwin and Stokols (1988) used this model to describe the effects of environmental stress. > stress represents perturbations in the system, and most stress theories posit some sort of coping mechanism as a way of maintaining homeostasis. > however, if a stressor is sudden, severe, and cuts across different domains, it is likely to provoke deviation amplification processes and result in long-term change, whether negative or positive.

Types and nature of heat shock proteins (Hsps): Molecular/Cellular Theories of Aging (biological theories)

- In part, the function of Hsps depends on whether they are located, either within cells or in extracellular material - Hsps in extracellular material may be involved in tumorigenesis, as they can protect against apoptosis; thus, tumors may use them to promote growth - cancer patients who had higher levels of stressful life events and more negative moods had higher levels of circulating Hsps. - Circulating levels of Hsps decrease with age and higher levels are associated with increased frailty in late life

Evidence supporting programmed cell death (Apoptosis) - genetic theory (biological)

- In the 1960s, Hayflick and his colleagues (1977, 1996) performed a very interesting series of experiments showing that certain cell lines in vitro (or cultured in Petri dishes) showed finite numbers of divisions and that fetal cells replicated more times than adult cells did, as noted earlier. - Clearly, there is a link of some sort between number of possible cell replications and life span. > For example, there is an inverse relationship between the age of the donor and the number of cell replications; the cells of individuals with diseases characterized by accelerated aging, such as progeria, show fewer cell replications in vitro. > Thus, there may be a rough correlation between the life span of a species and the number of times a cell will replicate.

figure 3.3 An Ecological Model of Resilience p 55

- In this model, posttraumatic growth (PTG) is thought to develop with ''seismic'' stressors (i.e., major trauma such as combat exposure or life-threatening illness), while stress-related growth (SRG) is thought to develop in a broader array of stressful situations. - In both instances, through the process of coping with stress, individuals can build up more resources over time, which in turn can affect the social context. > For example, someone coping with breast cancer may start a local support group with the assistance of a national organization, which becomes a resource for others in the community.

Heat Shock Proteins: Molecular/Cellular Theories of Aging (biological theories)

- Just as there are DNA repair mechanisms to protect genes, there are many different types of cellular repair mechanisms, which can be considered aging decelerators. - The most important of these for the aging process may be Hsps, so-called because they were first identified in plants undergoing heat-related stress. - Within cells, they play a major role in protecting cells from nearly every kind of stressor, from radiation to infection to oxidation. - The importance of Hsps is signaled by the fact that they are found in every living organism, from bacteria to humans, and in nearly all types of cells. - In addition to protecting cells against the effects of stress, they also are important in promoting healthy cell growth and proliferation

Current Theories: Self-Directed Development

- Langer and her colleagues (1990) argued that development in adulthood consists of increasing mindfulness * Langer defines mindfulness as consisting of three characteristics > continuous creation of new categories > openness to new information > implicit awareness of more than one perspective - mindlessness is characterized by an entrapment in old categories, by autonomic behavior, and by awareness of only a single perspective - Levenson and Crumpler (1996) proposed a liberative model of adult development that defined adult development as increasing freedom from social and biological conditioning - Brandstädter et al. (2010) presented an elegant set of experiments that suggest that recognition of death influenced the development of a "decentered" perspective in late life, similar to self-transcendence - Self-transcendence may be linked to resilience and other measures of well-being in late life, especially for women

Genetic Theories of Aging : aging acceleration theories

- Many genetic theories of aging specify what can go wrong, thus, these can be classified as aging acceleration theories - Most dramatic example proposes the existence of a death gene: gene that regulates sudden cell death, a process that is also called apoptosis - Rather than actual programmed death, geneticists such as Hayflick have argued that there may simply be a limited number of times that a cell can replicate without error, thus, aging may be a function of random (or stochastic) errors - DNA can be repaired, which can be considered a protective mechanism against aging: 1) in the process of replication, there are several different checkpoints through which a cell checks the integrity of the DNA strands. If an error is caught, replication is stopped so that repairs can be made 2) base excision repair, nucleotide excision repair, mismatch repair, and repair of strand breaks - Caloric restriction has been shown to promote longevity through several mechanisms: 1) delaying age related disease, including cancer and neurodegenerative disease 2) mediated through regulating gene expression, especially those responsible for energy regulation, gene transcription, and mitochondria

deviation amplification theories

- Many genetic theories of aging specify what can go wrong; thus, these can be classified as deviation amplification theories. - The most dramatic example proposes the existence of a death gene: a gene that regulates sudden cell death, a process that is also called apoptosis.

Mindfulness: Self-Directed Development

- Mindfulness is another hot topic/buzzword in psychology. - Ellen Langer was probably the first psychologist to entertain this idea. - A clinical psychologist named Mark Williams is one of the leaders in the field; he has worked with everyone from the Dali Lama to the United Nations to introduce Mindfulness and a pathway to individual development. - The characteristics listed above are core concepts in most approaches to mindfulness. - Aging research on this concept doesn't fit perfectly into any of the earlier models, Aldwin and Gilmer use the term self-directed, which is close to the concept of self-regulation.

Current Theories: psychosocial theories of aging

- Most current theories take some sort of middle ground between strict sociogenic and ontogenetic stances, but they do so with varying emphases on the context, individual goals, and agency (the individual's choice or ability to influence the situation). - Most attempt to integrate biological, psychological, and sociohistorical influences on development in adulthood.

Caloric Restriction and the Upregulation of Longevity Genes: genetic theories of aging (biological theories)

- Much of what we have learned about genes that promote longevity stem from caloric restriction studies, which examine the effect of nutritionally complete but calorically restricted diets. - In several species, caloric restriction has been shown to promote longevity through several mechanisms (Greer & Brunet, 2011). > In part, it does this through delaying age-related disease, including cancer and neurodegenerative illnesses. - The mechanisms are complex and may vary across species and dietary regimens (i.e., caloric restriction vs. protein or carbohydrate restriction). > However, the pathways do seem to be mediated through regulating gene expression: especially those responsible for energy regulation, gene transcription, and mitochondria. - R. A. Miller's (2009) review identified some 12 different gene mutations that affect longevity. > In part, these genes typically allow animals to respond to environ- mental poverty (e.g., relative absence of nutrition) to slow growth and metabolic rates.

Wear-and-Tear Theories: System-Level Theories (biological theories)

- One of the earliest theories of aging was the simple wear-and-tear theory: with continual use our organs and joints simply wear out. - For most organ systems, this early theory does not hold. > ex. if this were true, then athletes should have shorter lives than sedentary individuals, which does not appear to be the case - many systems such as the cardiovascular system need regular, moderate exercise to maintain function, and intellectual stimulation may be necessary to the maintenance of cognitive function > Indeed, the most common phrase in gerontology today seems to be ''use it or lose it.'' - The one exception to this adage (''use it or lose it.'') appears to be skeletal joints. > One of the causes of osteoarthritis is wear and tear on the joints, and osteoarthritis is nearly universal in late life. > However, it is also true that total bed rest in the elderly can result in stiffened, immobile joints (contracture), as well as problems with a host of other systems, including the cardiovascular, gastrointestinal, genital-urinary, respiratory, endocrine, metabolic, and neuropsychological systems (Fishburn & de Lateur, 1996). - Under most conditions, then, moderate usage is far preferable for organ functioning. - abuse of a system will shorten its life span. > ex. athletes with high levels of injury may shorten the effective life spans of several of their organ systems. > problems with the skeletomuscular system in professional football players are legendary, as are neurological problems in professional boxers who have sustained many concussions.

Oxidation: Molecular/Cellular Theories of Aging (biological theories)

- One of the most popular theories of aging is the free radical theory. - Free radicals or reactive oxygen species (ROS) are molecules that are generated during the oxidation process in cells. - Each ROS has an unpaired electron; thus, they are unstable and extremely chemically reactive. - Quinlan et al. (2011) distinguish between two forms of the ROS theory. - The simpler form of the theory holds that ROS can interfere with the functions of other molecules in the cell, including DNA replication, the metabolism of fatty acid chains, and protein synthesis. > In part, free radicals such as superoxide can damage proteins by causing them to unfold; without their proper conformation (structure), proteins cannot perform their functions correctly. > ROS may also interfere with DNA and DNA transcription and eventually lead to cell senescence. > As mentioned earlier, mtDNA are particularly vulnerable to ROS. - The slightly more complicated form is a ''vicious circle'' model (e.g., deviation amplification), in which the ROS damage the mitochondria. > The damaged mitochondria generate more SOS, leading to further damage, and so on.

Goal-Oriented Models: current theories

- P. B. Baltes (1987) characterized development in adulthood as a balance between gains and losses, with relatively more gains in early adulthood and more losses later. - Like Erikson (1950), Baltes proposed a life span (as opposed to life course) theory, and the dynamic between gains and losses is reminiscent of Erikson's dialectic between positive and negative outcomes. - However, Baltes did not propose a series of stages but instead argued for a process approach that describes adaptation to aging. > Successful aging is characterized by selection, optimization, and compensation (SOC; Baltes, 1997). > Assuming that older individuals have fewer resources, they must select the goals or activities they wish to pursue and optimize their performance by devoting resources to those particular goals. > They may also compensate for any deficiencies that could prevent them from achieving their goals. > A classic example of the SOC process is the pianist Arthur Rubinstein, who performed well into his 80s. * He was able to maintain his career by decreasing his repertoire, selecting those pieces he felt most capable of performing, and optimizing his performance by practicing these fewer pieces. * To compensate for neurological slowing with age that affected the speed with which he could play demanding pieces, he would slow down the passage just before one with a fast tempo, which made it seem as though he played the following passage faster than he actually did. - Brandtsta ̈dter's (1999) self-development model also emphasizes goals but argues that there are developmental changes in goals from young adulthood to late life. > The goal in early adulthood is to achieve the ideal self, which is largely culturally determined. In later life, however, the goal becomes to maintain the self as much as possible, as a means of preserving resources and counteracting developmental losses. - Brandtstadter, Wentura, and Rothermund (1999) have shifted from simply describing changes in the types of goals in adulthood to hypothesizing that development in adulthood consists of self-directed development in pursuit of goals.

Genetic Theories: biological theories of aging

- Probably the best evidence for genetic theories of aging is the relatively fixed differences between species in length of life span. - The maximum life span of a human is about 120 years, whereas that of a fruit fly is about 30 days. - In general, life spans appear to be inversely related to various factors such as metabolic rate, length of time to maturation (especially sexual maturity), response to stress (Jazwinski, 1996), and relatively smaller stature (Miller, 2009). - We are beginning to understand the very complex mechanisms through which genes regulate aging and death. - A central dialectic, though, is whether aging is a complex, multifaceted process that may differ not only across species but in subgroups within species (Aviv, 2011), or whether there may be one or two unifying processes that link highly diverse aging processes (Miller, 2009).

System-Level Theories: Stress

- Prolonged exposure to stress, both physiological and psychosocial, may increase the rate of aging in various organ systems - Stress related hormones and catecholamines can have toxic effects - Physiological stress resistance, especially the resistance to oxidative stress, is a significant factor in longevity - Hormesis: phenomenon in which moderate exposure to toxins or other physiological stressors may promote future resistance to stress and enhance longevity - Stress is a new comer to theories of aging and has not received as much research attention, however, it is increasing because of the general increased interest in stress. - Of course we don't really know what stress is, so that's the first issue these theories must address. - note that there is evidence for both the damaging effects of stress and the potential positive influence of moderate levels of stress. - as we grow older the trick is to find the balance point between moderate stress and longevity.

Evidence for Oxidation: Molecular/Cellular Theories of Aging (biological theories)

- Quinlan et al. (2011) reviewed the evidence for these theories and found that it is somewhat mixed. - 4 lines of evidence that support the ROS theory of aging: 1) longer lived species' mitochondria produce few free radicals 2) increasing levels of free radicals in lipofuscin (cellular waste products) with age 3) the correlation between oxidation levels and deletions in mtDNA 4) muscles with sarcopenia (atrophy) have mitochondria with lots of mtDNA damage. - There is some evidence for the ''vicious cycle'' theory, in that cells with damaged mtDNA do generate more free radicals. - However, there are other lines of evidence, which, surprisingly, do not support the ROS theory of aging. ' > 'Knockout'' mice (those who are genetically altered to delete a gene) with mtDNA mutations and deletions do show accelerated age-related illnesses such as sarcopenia, osteoporosis, and alopecia (hair loss), but they do not necessarily show more evidence of increased ROS. > Further, damaged/aged muscle cells may emit fewer ROS, as they may be processing less oxygen. - Quinlan et al. (2011) argue that there is actually better evidence for the protective effects of antioxidants such as superoxide dismutase (SOD) and catalase. > Antioxidants are compounds that can counter the effect of ROS by absorbing the extra oxygen ion or pairing it to increase stability in the molecule. > For example, knockout mice missing manganese super oxide dismutase (Mn-SOD) are short lived and have aging-related illnesses such as anemia, cardiomyopathy, neural degeneration, and evidence of oxidatively damaged mitochondria in very active tissues. > Further, mice who overexpress Mn-SOD live slightly longer, but this does not appear to be me- diated by fewer ROS. > Better results are seen with genetically altered mice that overexpress catalase. - Thus, there appears to be partial but not complete support for the ROS theory of aging.

Stochastic Processes: genetic theories of aging

- Rather than actual programmed death, geneticists such as Hayflick (1996) have argued that there may simply be a limited number of times that a cell can replicate without error. - Thus, aging may be a function of random (or stochastic) errors. - Replication error is one of the leading theories of aging. - DNA is susceptible to damage by a host of environmental factors, including a variety of chemical agents (e.g., cigarette smoke) and radiation (e.g., background or cosmic radiation) as well as internal processes such as oxidation. - Damage to DNA can impair a cell's ability to synthesize proteins and other substances and/or respond to regulation. - For critical DNA sequences, there are often multiple backups. - Cells can limit this damage by turning off the damaged segment and turning on identical backup segments or by using DNA repair mechanisms to correct the error (see text that follows). > Eventually, however, the cell runs out of backups, and it can no longer function adequately. - One theory suggests that genomes may have a limited number of replications of different DNA strands. > Once all of the strands are damaged or the damage overwhelms the repair mechanisms, the cell becomes impaired and may replicate with this impaired segment. If too many cells in a particular organ system fail, the system can become compromised.

Sociogenic Models: Psychosocial Theories of Aging

- Rejects telos-driven (purpose-driven) development, focusing instead on change in adulthood that varies as a function of social roles and historical contexts - Neugarten and Datan presented a model that reflected the timing and acquisition of social roles as a way to structure the life course * was seen to be a much more flexible model because it allowed for the influence of social factors such as SES as well as gender differences in life course structure, which could result in cumulative advantages or disadvantages * gave rise to many different theories such as disengagement theory - According to these theories, change in adulthood is characterized by a succession of role transitions that are shaped by the immediate social context and larger social structure rather than by internal psychological processes - Strict sociogenic models began to give way to those recognizing that individuals are also agents who take an active role in structuring their life course

Resilience and Aging: current theories

- Resilience in adulthood and late life has recently emerged as a ''hot topic'' in the field of adult development and aging, with four edited volumes recently published (Fry & Keyes, 2010; Hayslip & Smith, 2012 ; Reich, Zautra, & Hall, 2010; Resnick, Gwyther, & Roberto, 2011). - Although resilience has long been studied in childhood, usually in the context of adversity (see Luthar, 2006; Masten & Wright, 2009), the adult perspective has been somewhat different. Allen, Haley, Harris, Fowler, and Pruthi (2011) defined resilience as ''the developmental process of being mindful of and prioritizing those behaviors, thoughts, and feelings that facilitate contentment within a specific developmental, physical, emotional and spiritual context'' (p. 2). > In contrast, WHO (2002) defined resilience as ''the process of optimizing opportunities for health, participation and security in order to enhance quality of life as people age'' (p. 12). - Space does not permit a discussion of the myriad of different approaches that have been taken, but we will focus on three that might prove most relevant to the study of aging and health. - The dynamic model of affect (DMA; Zautra, Arewasikpom, & Davis, 2010) is not specific to aging but is nonetheless highly interesting. > Zautra et al. (2010) proposed that, in general, positive and negative affect are orthogonal. > However, they become more unidimensional under stressful conditions, with positive and negative affect inversely associated. > Resilient individuals are those who are more likely to maintain orthogonality of positive and negative affect under stress. > It is likely that this is through the use of coping strategies such as humor and social support. - Charles (2010) and Aldwin, Park, and Spiro (2007) both noted an interesting conundrum in the aging literature, namely, older adults are physiologically more vulnerable to stress and respond more adversely to stressful stimuli in laboratory settings (such as injections of epinephrine), but, in field studies, they often show less vulnerability to stress. > They both posited that older adults appear to be better at regulating emotions, especially in interpersonal settings (see Berg & Upchurch, 2007). > In part, the better regulation may stem from long experience with the variety of stressors faced in a long life. - The two models differ in that Turk Charles (2010) focused on the impact of time perception, whereas Aldwin et al. (2007) focused on appraisal. > In Turk's model, the realization that one has only a finite time left to live, derived in part from experiencing the loss of loved ones, allows the older adult to have greater clarity in the relative importance of problems. > In contrast, Aldwin et al. (2007) focused on the larger perspective and positive coping strategies gained from dealing with prior stressors. However, both conclude that these factors influence older adults' appraisal of stress, which generally tends to be lower than that of younger adults. > In other words, physiological regulation of the stress response is poorer in late life, so older adults have learned that it is better not to perceive things as problems, or to discount their stressfulness, in order to avoid heightened arousal and distress. > In other words, older adults, knowing that they have hypertension, heart conditions, and other chronic illnesses, consciously adopt appraisal and coping strategies that promote better regulation, because they realize the adverse physical consequences of allowing themselves to become upset. - Aldwin and Igarashi (2012) extended this model to a more general theory of resilience in late life (see Figure 3.3). > They posited that resilience is not simply a matter of individual resources but involves a complex transaction among sociocultural, contextual, and individual resources, all of which can affect and be affected by individuals' coping strategies in stressful situations. > When individuals cope with stress, they draw upon immediate resources available to them, as well as longstanding ones, generalized resistance resources (GRRs; see Antonovsky, 1979). * GRRs reflect individual resources (such as intelligence, calm disposition, and financial resources) as well as contextual ones (such as social support) and sociocultural resources (e.g., the availability of good health care, positive attitudes toward aging).

Resilience

- Resilience is a current buzz word in the aging literature or as the slide says hot topic. - It actually started in the study of trauma and infant development. - It is a little too buzzy for me. - The topic does not have clear measures. - It is something that we infer from what happens to people after they have been exposed to a severe threat or to a prolonged series of threats to their well-being. > The hurricanes of the past few weeks are a challenge to the resilience of millions of people. - Resilience can occur at many different levels including strictly physical and strictly psychological. - One of these ideas is something called post-traumatic growth. > As the name implies this refers to the hypothesis that some individuals show various forms of "improvement" following the exposure to trauma. > A controversial idea is that an individual can show both negative and positive outcomes following a traumatic event. > An unanswered question is what individual characteristics favor this sort of resilience

Stress: System-Level Theories (biological theories)

- Stress models of aging are a modern reincarnation of the wear-and-tear theories. - There is growing evidence that prolonged exposure to stress, both physiological and psychosocial, may increase the rate of aging in various organ systems, as stress- related hormones and catecholamines can have toxic effects - Reactivity to stress tends to have deleterious effects, because it is associated with prolonged exposure to stress-related hormones and catecholamines. - According to Brown-Borg (2011), physiological stress resistance, especially the resistance to oxidative stress, is a significant factor in longevity, as it may decrease the oxidative damage - . There are many pathways to stress resistance, including a variety of antioxidant enzymes mentioned earlier, such as catalase, SOD, and glutathione. > Because GH is an anabolic factor, it increases cellular metabolism, including oxygen and glucose consumption, which leads to increased ROS. > GH and IGF-1 decrease the levels of antioxidative enzymes depending on the type of tissue. Other types of stressors to which GH-deficient species are resistant include hydrogen peroxide, cadmium, heat stress, and UV light. > They also might have higher levels of Hsps, metal chelators, and enzymes involved in protein repair and are also resistant to carcinogens.

Interrelationships Among Levels of Analysis

- The different levels in biological theories of aging (genetic, molecular/cellular, and systems level) are linked. * the authors use the term transaction to describe how cells and organ systems influence each other. (economics analogy of give and take, I give you money, you provide a service) - Plasticity in the system allows for intervention and the use of agents to delay aging but also may result in cascades that accelerate aging. * this ties to stress theories. * we know that the psychological experience of stress can contribute to the acceleration or aging, and the control of stress through exercises such as mindfulness can decelerate the impact of stressful experiences. - As a theoretical model of aging, focusing on inflammatory processes has the potential to integrate across the genetic, molecular, cellular, and ecological levels. * the HPA axis is the target of much recent stress research. - Incorporating these new ideas into a general theory of aging is taking place as we read about it here.

System-Level Theories: Homeostasis and Balance

- The first two system level theories are focused on the processes of homeostasis and balance (rhythm) theories. - These two ideas are related to one another, and have been described as "a chicken and egg problem." > This means we are not sure if homeostasis issues cause rhythm problems; Or if rhythm problems disrupt homeostasis. - For our purposes, what we want to understand why older adults have some characteristic problems. > One is orthostatic hypotension: this refers to a rapid decline in blood pressure when a person stands up. * Standing up creates a "cascade" of reactions in the body that challenge the blood pressure system. * As we age our ability to deal with this cascade produces a rapid decline in blood pressure. This produces dizziness, which contributes to the high rate of falling. > Type II diabetes is another problem of a cascade of changes that the older body cannot regulate properly. * The onset of Type II diabetes is accelerated by obesity.

Molecular/Cellular Theories of Aging: Oxidation

- The most important point in this section is that the influence of oxidation is not a settled matter. - Especially in humans, the species that has probably received the least amount of attention. - To some biologist this makes a very compelling study but to others it is not supported by some of the most important and well-conducted researcher. - Now there is even evidence that at least in some circumstances oxidation may serve as an age decelerator! - This is potentially very relevant to human beings, especially for those of us with a sweet tooth because sugar promotes oxidative stress. - There are plenty of reasons not to eat in too much sugar, so even if free radical theory is not correct it's a good idea not to eat it. - Apparently taking it in the form of high fructose corn syrup is a bad idea, so soda manufacturers are going back to regular sugar and using the corn to feed cattle, hogs, and our gas tanks (ethenol).

The ontogenetic theories

- The ontogenetic theories such as Freud and Erikson come first historically. - Freud pretty much ignored aging processes. He believe personality was formed early in life, did not change to any great extent as we matured, and that older people should not go through psychoanalysis because it was a waste of the analysts time! - The book tries to emphasize a theme the Erikson emphasizes in the quote presented on page 49: "each stage brings with it positive features and negative features. We struggle with the balance of these throughout life once the dichotomy is introduced into our personality." > In a way, this is a gain and loss theory. > Once the stage of trust v. mistrust is introduced, it allows for the gains of trust, but also the losses of mistrust. - The weakness of Erikson is that his theory doesn't help us to understand how context factors like social class, education, politics are incorporated into the individual's struggle to balance these two in a favorable way. > This is where more contemporary researchers like Whitbourne come in.

Sociogenic Models: psychosocial theories of aging

- The ontogenetic theorists were strongly criticized for positing one primary goal or developmental pathway and ignoring differences in life courses due to gender, social class, culture, and cohort (see Rossi, 1980). - Sociogenic models eschew telos-driven development, focusing instead on change in adulthood that varies as a function of social roles and historical contexts. - Neugarten and Datan (1973) presented a model that reflected the timing and acquisition of social roles as a way to structure the life course. - Transitions that follow social norms are considered to be on time, whereas those that occur earlier or later than normal are off time and therefore much more difficult. > For example, it is much easier for a woman to start a family when she is in her 20s than in early adolescence or midlife. - This was seen as a much more flexible model, because it allowed for the influence of social factors such as SES as well as gender differences in life course structure, which could result in cumulative advantages or disadvantages (Dannefer, 1984; Moen, 1992). - This gave rise to many different theories such as disengagement theory (Cum- mings & Henry, 1961), which posited a mutual withdrawal between the individual and society as one ages. > Disengagement theory was countered by activity theory (Havighurst, 1961), which argued that the more active the older person is, the greater the life satisfaction. Havighurst, Neugarten, and Tobin (1968) resolved this controversy by demonstrating that the moderating factor is personal desire: the activity level preferred by older adults. > In other words, those who want to be active but cannot be are unhappy, whereas those who do not want to be very active but are forced to be by their circumstances are also unhappy. > For example, someone who wants to keep working but is forced to retire may find retirement stressful, and someone who would like to retire but cannot due to lack of adequate pensions and savings may find working stressful. - Thus, according to these theories, change in adulthood is characterized by a succession of role transitions that are shaped by the immediate social context and larger social structure rather than by internal psychological processes. - However, strict sociogenic models began to give way to those recognizing that individuals are also agents who take an active role in structuring their life course (see Clausen, 1995).

Functions of heat shock proteins (Hsps): Molecular/Cellular Theories of Aging (biological theories)

- There are several different types of Hsps, which have a variety of functions. - Functions: 1) They are also called ''molecular chaperones'' because they assist in protein synthesis and repair. 2) Small Hsps protect cells from stress and oxidative processes by regulating enzymatic processes necessary for repair and apoptosis; others refold damaged proteins into their proper configurations 3) They also play a major role in the inflammatory process including active recruitment of immune system cells such as macrophages and neutrophils to attack bacteria or virus-infected cells - Although the inflammatory process is usually necessary for healing, it can damage surrounding healthy tissue if unregulated. - Hsps are one of the mechanisms that control inflammation. - If they cannot repair a cell, they may help the cell to self-destruct, ''choosing'' between apoptosis and necrosis. - In apoptosis, a cell systematically dismantles and repackages itself and is readily reabsorbed by the surrounding cells. - in necrosis, the cell ruptures, spewing toxic chemicals and distress signals, leading to an increase in the inflammatory process. - Hsps may aid in the healing process by dismantling damaged cells, or they may contribute to chronic inflammation (and perhaps autoim- mune disorders) by mechanisms that are as yet poorly understood.

self-directed development: current theories

- There is a growing sense that adult development is something that individuals do, not something that simply occurs. - Langer and her colleagues (1990) argued that development in adulthood consists of increasing mindfulness. - Langer (1997) defines mindfulness as consisting of three characteristics: 1) the continuous creation of new categories 2) openness to new information 3) implicit awareness of more than one perspective. Its counterpart, mindlessness, is characterized by an entrapment in old categories, by autonomic behavior, and by awareness of only a single perspective. - The development of mindfulness is not automatic with age but reflects a process of conscious attempts to increase awareness and think in more flexible ways. - Levenson and Crumpler (1996) proposed a liberative model of adult development that defined adult development as increasing freedom from social and biological conditioning. > It differed from earlier models in suggesting the way in which this occurred. - In the liberative model, the method of development is based on self-observation. > Through self-observation, one can become aware of negative characteristics that can constrain understanding and behavior, limiting one's choices of action. (Note that positive characteristics may also be constraining.) - Levenson, Aldwin, and Cupertino (2001) have argued that loss plays a central role in adult development, as it can force individuals to examine their own assumptions and develop new and more mindful ways of being. > They suggest that this is the process that underlies Tornstam's (1994) observation of gerotranscendence in late life, which is similar to Peck's (1968) construct of ego transcendence and is characterized by less rigid ego boundaries (a sense of oneness or connection with the universe) coupled with a decreasing reliance on others for life satisfaction. - Brandtsta ̈dter, Rothermund, Kranz, and Ku ̈hn (2010) presented an elegant set of experiments which suggest that recognition of death influenced the development of a ''decentered'' perspective in late life, similar to self-transcendence. - Further, Jennings, Aldwin, Levenson, Spiro, and Mroczek (2006) found that moderate combat exposure, as well as appraisal and coping processes, led to the development of self-transcendence in later life.

Interrelationships Among Levels of Analysis: biological theories

- These different levels of analysis in biological theories of aging (genetic, molecular/ cellular, and systems level) are linked. - Perturbations at the genetic level affect cellular functioning, which in turn affects the ability of the system as a whole to maintain homeostasis. - Similarly, problems in maintaining homeostasis, such as stress reactivity, may cause damage at the cellular and genetic levels. > Thus, the rate at which organisms age is affected by a host of factors that are not necessarily linked in unidirectional causal chains but rather interact or transact in highly complex fashions. > This plasticity in the system allows for intervention and the use of aging decelerants but also may result in cascades that accelerate aging. - It is becoming increasingly clear that the plasticity in the system also allows for psychosocial influences, both positive and negative. - One of the most exciting new theories of aging centers around inflammation and explicitly addresses how the various levels in aging research can be integrated (see Finch, 2011 for a review). > Inflammation refers to an array of protective responses that an organism generates to combat infectious agents and/or to protect an injured area. > Classic symptoms of inflammation include redness, swelling, and heat. > The redness reflects increased blood flow as the body tries to deliver more protective agents to the area; the swelling or edema is a result of increased lymph-carrying immune components; and the heat is due either to action by the mitochondria in the local area or a systemic fever. > These processes may be acute: as in a reaction to a bee sting or twisted ankle, or they may become chronic. >Finch (2011) argued that inflammation is a core aging process because it is involved in both primary aging and chronic disease processes, including atherosclerosis, Alzheimer's disease, and cancer, as well as diseases of the joints. > Inflammation involves a highly complex series of biochemical reactions that may be stimulated by ROS and, at the cellular level, may be involved in cell senescence. > In addition, inflammation is regulated at the systems level by the hypothalamic-pituitary-adrenal (HPA) axis as well as the nervous system, which are central to the feelings of pain and lethargy associated with inflammatory processes. > Further, some of the genes that influence longevity also regulate inflammatory processes. > Interestingly, inflammatory processes are also linked to lifestyle factors such as nutrition, exercise, obesity, as well as to environmental factors such as air pollution and exposure to toxins. > Thus, as a theoretical model of aging, focusing on inflammatory processes has the potential to integrate across the genetic, molecular, cellular, systems, and ecological levels.

Sociogenic Models

- These theories are more popular in sociology than in psychology, but they do provide some valuable insights for psychologists. - They locate the influences on behavior more in the current external environment than in the ontogenetic history of the individual. - Roles are governed by scripts that are part of the social knowledge of a culture. * No one writes down the history of these roles and the changes that take place in the meaning of these roles over time. - The idea from the sociogenic models that probably has had the most influence in psychology is the Neugarten and Datan notion of on time and off time. * On time transitions are much easier for the individual than off time. > Consider a 14 year-old girl whose mother dies, leaving her in charge of the hoursehold and child-rearing responsibilities. > This is a much more difficult transition than getting married at 23, having children, and transitioning into the parent role. > What ontogenetic theorists would say is that the increased difficulty of the 14 year-old is partly due to her ontogenetic level of developmennt - The last point on the slide reflects the view of the authors and they do not spell it out very well: "strict sociogenic models began to give way to those recognizing that individuals are also agents who take an active role in structuring their life course" > I have to say that many sociogenic theorists would not agree with their connection to agentic theories.

Homeostasis and Balance Theories: System-Level Theories (biological theories)

- To function, organisms must maintain a certain level of homeostasis, that is, stability in intracellular and extracellular environmental conditions, such as pH balance, blood pressure, heart rate, temperature, and electrolyte and fluid balance. - Nearly all conditions fluctuate in response to environmental demands but then must return to baseline levels. - Homeostasis requires communication among the various organ systems and is largely regulated by the autonomic nervous system via the neuroendocrine system. - There is good evidence to suggest that, as we age, it becomes harder to maintain homeostasis - A number of systems in the elderly show slower responses to environmental challenges but may eventually show heightened responses that take much longer to abate and return to baseline. > This may be due to both disease-related and intrinsic age-related processes, which may be difficult to disentangle. - Problems in homeostatic regulation may be due to one of three factors (which also may work in combination): 1) there may be a decline in the production of hormones or other type of regulatory peptides. - Ovarian decrease in estrogen production is a good example of this. 2) the target organs may become less responsive, due either to fewer receptors for neuroendocrine signals or to degradation in the functioning of receptor sites on cell surfaces. - For example, receptor cites for insulin may degrade with age (a process hastened by obesity). 3) the target organ may synthesize less than optimal amounts of its product, due either to fewer secretory cells or to less efficient production. - Thus, the system may respond sluggishly, causing more difficulty in maintaining adequate homeostasis. - A number of illnesses commonly associated with aging reflect these problems in homeostasis, such as orthostatic hypotension (failure to maintain sufficient blood pressure when standing up) and diabetes (failure either to produce sufficient insulin or for insulin receptor sites to respond adequately;

System-Level Theories: Homeostasis and Balance Theories

- To function, organisms must maintain a certain level of homeostasis, the stability in intracellular and extracellular environmental conditions such as pH balance, blood pressure, heart rate, temperature, and electrolyte and fluid balances - As we age, it becomes harder to maintain homeostasis - Problems with homeostatic regulation may be due to one of three factors (which may work in combination): 1) decline in the production of hormones or other type of regulatory peptides 2) target organs become less responsive, either because of fewer receptors for neuroendocrine signals or because of degradation in the functioning of receptor sites on cell surfaces 3) target organ may synthesize less than optimal amounts of its product, either because of fewer secretory cells or less efficient production - Aging is association with changes in temporal organization of physiological rhythm - Balance between anabolic and catabolic processes: 1) catabolic processes are growth related, whereas anabolic processes are those that are involved in breaking down structures 2) one theory of aging argues that growth occurs when catabolic processes dominate 3) as seen with caloric restriction, suppressing GH, IGF-1, and insulin pathways results in decelerated aging 4) centenarians and other long-lived populations often show heightened insulin sensitivity and alterations in the GH, IGF-1, and/or insulin pathways

caloric restriction and longevity in humans: genetic theories of aging (biological theories)

- Whether caloric restriction increases longevity in humans, however, is still a matter of debate. - Although caloric restriction does improve things like insulin resistance and atherosclerosis, animal models suggest that caloric restriction must begin in adolescence or early adulthood to affect longevity (Greer & Brunet, 2011). - Anecdotal reports, though, suggest that it is difficult for humans to remain on a calorie-restricted diet, with many complaining of extreme fatigue. - Further, in humans, low weight in middle age and late life is associated with decreased longevity (Spindler, 2010).

System-Level Theories: Wear-and-Tear Theories

- With continual use, our organs and joints simply wear out - Theory does not hold true for most organ systems - Skeletal joints are an exception - Under most conditions, moderate usage is far preferable for organ functioning - Wear and tear theories are among the oldest theories. > Partly this was inspired by the apparent increased life expectancy of certain classes of people who did very little physical activity. > As a general theory, wear and tear does not work too well. > It may explain the deterioration of our joints, but this may be better thought off as injury/disease brought on by overuse, rather than acceleration of aging.

Programmed Cell Death (Apoptosis): Genetic Theories (biological)

- apoptosis proposes the existence of a death gene: a gene that regulates sudden cell death, - Genetic material is not static: different segments turn on and off depending on the need to synthesize proteins; perform other functions such as motility and transport; or to control the functions of other genes, including the complicated process of cell proliferation and regulation. - Damage to these regulator proteins may be one mechanism for the development of cancer, that is, uncontrolled cell proliferation. - But cells may also be turned off, failing to produce needed substances. - Apoptosis is one mechanism for the destruction of cells that have proliferated for specific purposes, such as T cells in the immune system, and need to be destroyed after having accomplished their task. - Researchers have found evidence for senescence genes, including one mortality factor simply called '' MORF'' (Campisise, 2001), which appears to control the rate of a cell's aging.

DYST: dynamic systems theory

- came from transactionalism

DST: developmental systems theory

- came from transactionalism - takes a ''multidisciplinary approach that seeks to integrate variables from biological through cultural and historical levels of organization into a synthetic, coactional system'' - This perspective takes a person-centered approach, which emphasizes individual differences in trajectories across the life span as well as plasticity or malleability in developmental processes. - This plasticity reflects individuals acting in concert with contextual and biological influences to influence developmental trajectories. - Thus, aging cannot be reduced to biochemical reactions in the cell, nor to lifestyle behaviors. - Rather, it represents complex, dynamic transactions among factors ranging from genes through cellular mechanisms through organ systems, psychological attitudes and behavior, and sociocultural structures and processes. - Tracing out pathways of mutual influence provides a fascinating look into the processes by which aging occurs and thus allows us to identify factors that accelerate or delay the rate of aging.

anabolic and catabolic processes (balance theory): System-Level Theories (biological theories)

- catabolic processes are growth related, whereas anabolic processes are those that are involved in breaking down structures, such as cell dismantling. - One theory of aging would argue that growth occurs when catabolic processes predominate, and aging occurs when catabolic processes are predominant. > However, there is some evidence that the suppression of some aspects of the somatotropic axis, consisting of growth hormone (GH), insulin- like growth factor 1 (IGF-1), and insulin actually contribute to greater longevity (Brown-Borg, 2011). > As we have seen with caloric restriction, suppressing these three pathways—GH, IGF-1, and insulin—results in decelerated aging. > Suppression of these pathways results in smaller size, delayed puberty, reduced metabolic rates, lower percentages of body fat, reduced incidence of cancer, and perhaps enhanced stress resistance. > In general, the mechanism appears to involve insulin levels and heightened insulin sensitivity. > Centenarian and other long-lived populations often show heightened insulin sensitivity and alterations in the GH, IGF-1, and/or insulin pathways.

DNA Repair Mechanisms: genetic theories of aging (biological theories)

- damaged DNA can be repaired, which can be considered a deviation-countering mechanism for aging. Many different factors can damage DNA, including light, ultraviolet (UV) and other types of radiation, exposure to toxic chemicals, and the oxidation process itself. - We do not know how the cell recognizes errors in the DNA structure, but we do know that damage tends to activate transcription and replication (Friedberg, 2000). - In the process of replication, there are several different checkpoints through which the cell checks the integrity of the DNA strands. If an error is caught, replication is stopped so that repairs can be made. - There are several mechanisms of DNA repair: 1) base excision repair 2) nucleotide excision repair 3) mismatch repair 4) repair of strand breaks. - Sometimes the errors escape detection, but at other times the damage can be tolerated, and the cell uses replication bypass (presumably, it simply skips over the error). If the error burden is too severe, the cell undergoes apoptosis. - Miller (2009) has argued that the types of mutation that extends life span in invertebrates tend to be those that increase resistance to toxins and in general increase stress resistance. > These include DNA repair mechanisms and resistance to free radicals. >However, we have learned a great deal about single gene mutations which can extend life span via a different mechanism: the regulation of metabolism, discovered in examining the effects of caloric restriction.

biological theories of aging (there are more than a dozen)

- discussing biological theories most relevant to the deviation countering/amplification framework. - categorizing biological theories of aging; 1) genetic 2) molecular/cellular 3) system-level theories. - Note that these theories are not mutually exclusive but rather provide a snapshot of the aging process at different levels of analysis.

The Life Course theory

- emerged from the sociology of aging, especially the work of Bernice Neugarten, Robert Havinghurst and Hagestad, referred to as the Chicago school because they were all affiliated with the University of Chicago. - This school of thought sees our behavior through a complex set of viewpoints: 1) First there is our immediate social context. What is going on around us right now? Are you sitting in class? On a bus? > These immediate contexts set limits on our behavior. 2) But there is also the context of the current social, political, and cultural environment in this particular year. 3) And then there are the more enduring social roles that we occupy. - Somehow all of these influences become integrated. - Elder did his original research on the influence of the Great Depression on child and adult development. > Since then he has developed models that are capable of evaluating the influence of the cohort (generation) that we belong to, along with the historical moment that may influence all generations in a similar way. - Settersten and Hagestad have tried to explain how multiple influences come to influence our behavior. > They talk about shared meanings. > The clearest example of shared meaning are found in language. The speakers of a given language "agree" on the meaning of words. > Non verbal communication is another place where shared meanings are clear. > Here we are talking about high levels of meaning that take the building blocks and put them together into more complex meanings. * For example, if I say that someone is domineering, that is a meaning that I am assigning to behavior. If we are part of the same cohort os the same cultural group, we are likely to agree that the persons behavior fits with that label.

psychosocial theories of aging

- emphasis on theory has increased greatly in the past 10 years - Indeed, Bengston, Gans, Pulney, and Silverstein (2009) edited a handbook on the theories of aging. - Many of these theories focus on descriptors of the aging population or on the way in which age is embedded in the social structure, but the focus of this book is on developmental processes and factors that affect the rate of aging. > However, given that quality of life is also important, we briefly review some of the major psychosocial theories of aging before focusing on developmental processes.

The LSDS approach

- emphasizes individual differences in trajectories across the life span as well as plasticity in developmental processes. - Processes of aging are to some degree modifiable and modulated by a variety of factors, including oxidative processes at the cellular level, nutritional status, and psychological factors such as personality, stress, and health behaviors. > These mediators may be risk factors that accelerate the rate of aging or resilience factors that slow it. - On the whole, trajectories of health for most of the population have improved dramatically in the past 100 years (Schaie, 2005); more people are able to live longer and with fewer or delayed cognitive and physical disabilities. > nevertheless, there are large individual differences in the rate at which people age. - As Schaie (2005) noted, the rate of aging has slowed dramatically in the past 100 years, which means not only that individuals live longer but that their cognitive and physical declines have proceeded at a slower pace. - Changes in the rate of aging occur not only at the societal level but also at the individual level.

Aging processes

- occur at the biological, psychological, and sociocultural levels

Aging processes

- occur at the biological, psychological, and sociocultural levels. - we are beginning to identify different processes that govern or regulate the rate of aging. - these theories are often specific to the particular process being studied (e.g., genetic or molecular), and relatively few attempts have been made to bridge different theories or aging mechanisms.

Factors that contribute to the rate of aging.

- on a biological level, these include genetic factors such as longevity genes (e.g., silent information regulator 2 [SIR2]), epigenetic regulation of gene expression, heat shock proteins (Hsps), telomere lengths, oxidative processes in mitochondria, and the efficiency of apoptosis (Bos- tock, Soiza, & Whalley, 2009; Hekimi, 2000; Masoro, 2000). - On a psychosocial level, these factors include not only health behavior habits, such as drinking, smoking, obesity, and caloric restriction, but also personality processes such as hostility, anxiety/neuroticism, and conscientiousness, among others (Aldwin et al., 2006). - both biological and psychosocial stress and how individuals cope with them may also influence the rate of aging (Aldwin, 2007). - sociocultural resources, such as gerotechnology, may greatly affect functional health—how well individuals can function in everyday living despite physical impairments. > Gerotechnology allows individuals to be maintained in the community longer, effectively decreasing disability rates

FIGURE 3.1 Comparison of Three Different Types of Causal Models

- p 36 - TRANSACTIONALIST MODEL - INTERACTIONIST MODEL - REDUCTIONIST MODEL

applicability of systems theory approaches to developmental processes and aging

- the applicability of systems theory approaches to developmental processes and aging is clear. - Biological processes relevant to aging fall into two categories: 1) those that promote homeostasis and decelerate the aging process (such as DNA repair mechanisms and Hsps) 2) those that amplify the deviations and accelerate the aging process (such as free radicals). - Psychological and social theories often discuss positive changes with age, however, and it must be remembered that systems approaches may need to be applied to positive as well as negative changes. - Many of the psychosocial theories of aging interface with biological theories and may fit loosely in this framework. - Thus, in the past decade there has been substantial progress in the development of theoretical orientations that can be usefully applied to the process of aging.

hormesis (Stress): System-Level Theories (biological theories)

- there is also an exciting new line of research into a phenomenon called hormesis, in which moderate exposure to toxins or other physiological stressors may promote future resistance to stress and enhance longevity (Calabrese, 2008). - Johnson et al. (2002) note that all gene mutations that result in increased longevity in a species of worm studied extensively (Caenorhabditis elegans) do so by increasing the organism's resistance to stress

Transactionalism

- understands that phenomena are influenced by multiple factors that are not only influencing target phenomena but also influencing each other - also referred to a relational interaction, coaction, reciprocal bidirectionality, multi-directionality, or simply transaction - has given rise to relational developmental systems theory (RDST) - takes a person-centered approach, which emphasizes individual differences in trajectories across the life span as well as plasticity or malleability in developmental processes across multiple levels of analysis

The number of times a cell can replicate is regulated by...(Biological theories of aging)

1) In humans, the number of times somatic cells can replicate is partially regulated by the telomere length (for a review, see Aviv, 2011). - Telomeres consist of the specialized ends of DNA strands that help hold them together during mitosis. - The DNA strands do not completely unwind during mitosis but are held together by these caps at their ends, which do not replicate and thus are lost. - About 100 base pairs per cell are lost during each replication, and when several thousand base pairs are lost, the cell stops replicating and senesces (de Lange, 1998). > However, telomeres can be restored by an enzyme called telomerase, and indeed, cancer cells have much longer telomeres and more active telomerase than normal cells (except perhaps for those that need to proliferate extensively, such as epithelial cells in the intestine). - Aviv (2011) argues that shorter telomeres provide some protection against cancer, but ones that are too short can interfere with longevity and may result in infertility. - Interestingly, humans, as a species, have medium-length telomeres—shorter, for example, than mice. 2) The number of times a cell replicates may also be directly controlled by genes. - Researchers may have identified immortality genes that regulate cell senescence. - These were often identified in the course of cancer research. - Mutations in these genes may invoke immortality; that is, cells appear to replicate seemingly infinitely. - The nonmutated versions of these genes appear to regulate senescence (Ehrenstein, 1998).

Five principles of life-span developmental systems (LSDS) approach to health and aging

1) The goal of lifelong research is something we would like to see but it is very difficult to achieve. -There are a few institutions where this could be achieved such as the National Institute of Health, but the reality is that tracking people from prenatal development to death in later life means that we mostly try to approximate it by linking together studies of various different periods. 2) The term multidimensional is another great goal that is difficult to achieve. - For example, even within psychology, the people who study the brain may no very little about behavior, cognition, and emotion. - This means we need teams of researchers but this is seldom achieved. 3) Interdisciplinary means that a group of people from different disciplines attempt to understand the contribution or limitations to phenomena that are of interest, then the team develops a research plan based upon the diverse opinions. - Multidisciplinary means you have people from various disciplines working independently of one another on a common problem such as the impact of age on personality. 4) The idea of gains and losses is represented in this book better than most. The authors point out the shifting balance of gains and losses throughout the lifespan. 5) context dependent is another good goal that is tough to pull off. - For example, suppose we studied changes in memory with age. - This last point suggests investigators try to obtain information about the characteristics of the environment of participants. - A context question might be: What is their social class and what is the typical social class of their neighborhood

Five principles of life-span developmental systems (LSDS) approach to health and aging were delineated by Aldwin, Spiro, and Park

1) health is a lifelong process that begins before birth in the intrauterine environment 2) health is multidimensional - World Health Organization (WHO) defined health as "a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity" 3) the study of health must be interdisciplinary and preferably multidisciplinary 4) development consists of both gains and losses 5) aging is context dependent, meaning that contexts, such as SES and cultural settings, both support and constrain individual trajectories

Five principles of a life span developmental systems (LSDS) approach to health and aging were delineated by Aldwin, Spiro, and Park

1) health is a lifelong process that begins before birth in the intrauterine environment (Barker, 2005). - this process has genetic and epigenetic origins and, through all phases of life, results from gene-environment transactions, individuals' behaviors, and contextual influences such as socioeconomic status (SES) and cultural demands and resources. -thus, in order to truly understand aging, one must understand both how health changes over the life span and the factors influencing the trajectories of those changes. 2) health is multidimensional. - In 1948, the World Health Organization (WHO) defined health as ''a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity'' (WHO, 2002). - Health and aging processes are regulated by biological, psychosocial, and sociocultural factors, each of which has its own developmental trajectory. - Understanding the transactions among these factors is key to comprehending the processes by which rates of aging are regulated. 3) the study of health must be multidisciplinary and preferably interdisciplinary. 4) development consists of both gains and losses. - While biological aging research is generally focused on losses in capacity and adaptability, there may be gains as well, particularly at the psychosocial level, such as the ability for better emotion and self-regulation (see Aldwin, Yancura, & Boeninger, 2010). 5) aging is context dependent, meaning that contexts, such as SES and cultural settings, both support and constrain individual trajectories. - ex. those with lower SES in most countries generally have worse health behaviors, greater disability, lower well-being, less access to health care, and earlier onsets of morbidity and mortality (e.g., Adler & Snibbe, 2003). - Culturally prescribed attitudes toward aging and the elderly have also shown not just to affect adaptation to aging but also to the longevity of individuals; those with more positive attitudes tend to live much longer than those with negative ones > This emphasis on plasticity leads to the second basic theoretical perspective: individual differences in rate of aging: LSDS

psychosocial theories of aging: Classic Theories

Early on, the primary tension in theories of adult development was between the ontogenetic school, which posited that developmental forces are internal and probably biologically based, and the sociogenic schools, which argued that change in adult- hood is largely due to social forces. In general, ontogenetic scholars were based in Germany, whereas the sociologists who largely made up the sociogenic schools were influenced by French sociologists such as Durkheim, hence the headers in Figure 3.2.

reductionism

For the past 200 years, science has been guided very successfully by reductionism, which seeks to break complex phenomena into its component parts and examine causal processes

ppt

textbook starts flashcard 29

Ontogenetic Models: psychosocial theories of aging

- Classical ontogenetic models posit that development stems from internal forces and consists of stages that are universal, sequential, and irreversible. > Universal means applicable to everyone, regardless of gender, social status, or culture. - The stages are sequential, follow a definite order, and are thought to be irreversible; that is, they represent achievements. - In these models, change is discontinuous and is characterized by qualitative changes (as opposed to continuous, quantitative change). - Psychodynamic schools focused largely on personality development. > Ego psychologists such as Erikson (1950) modified Freud's psychosexual theory of early childhood to a psychosocial model that extended from birth through late life. > Erikson posited eight stages, ranging from basic trust versus mistrust, in early infancy, to ego integrity versus despair, in late life. > Adolescence and early adulthood are characterized by identity versus confusion and intimacy versus isolation, respectively, whereas midlife is characterized by generativity versus stagnation, with generativity involving caring for subsequent generations as well as the institutions that transmit culture across generations. > Each stage is characterized by a dialectic: a positive and a negative pole, and resolution of this dialectic sets the stage for positive or negative resolution of the next stage. > For example, it is hard to develop generativity if you have never learned to be intimate with anyone. > Erikson's theory is thought to satisfy all the requirements of a purely ontogenetic theory: positing qualitatively distinct stages that are thought to be universal, sequential, and irreversible. * However, closer reading of his original work shows that he perceived these stages more in terms of themes that are revisited at different ages in the life span. > As Erikson (1950) stated, In fact, some writers are so intent on making an achievement scale out of these stages that they blithely omit all the ''negative'' senses (basic mis- trust, etc.) which are and remain the dynamic counterpart of the ''positive'' ones throughout life. > The assumption that at each stage a goodness is achieved which is impervious to new inner conflicts and to changing conditions, is, I believe, a [dangerous] projection. (pp. 273-274) > This can complicate analyses examining change. * For example, Whitbourne and her colleagues (2002) found little aggregate change in generativity from young adult- hood to midlife, because the number of individuals who increased in generativity was balanced by those who decreased and presumably were stagnating. * Furthermore, some individuals increased and then decreased in response to changing life circumstances. - Erikson's (1950) caveat is important and requires more complex analyses than those examining simple aggregate change (see Chapter 4). - Other early theorists such as Peck (1968) and Vaillant (1977) elaborated in various ways on Erikson's (1950) basic paradigm. > For example, Vaillant added a ''career consolidation'' stage and characterized development in terms of changing defense mechanisms, whereas Peck added a further stage in late life that presaged some of the later work on transcendence (see below). - Jung's (1933) perspective on development was quite different from Freud's. > He focused on adult development, believing that adolescents and young adults develop a persona a false self developed to conform to adult social role conventions. > This involves suppressing aspects of the self that are socially unacceptable and emphasizing those characteristics that are socially desirable. > In Jung's highly gendered culture, young men were encouraged to emphasize masculine traits such as courage, suppressing their emotions, and focusing on career development. > In contrast, women were supposed to be feminine, nurturant, and focused on family. > From Jung's perspective, the goal of development in adulthood is to individuate, to abandon the persona, and become more of an individual. > Individuation involves the development of self-knowledge, bringing unconscious material into consciousness, and developing one's true capacities. - Jung believed that people who repress their true selves will find them reemerging in midlife. > Thus, men will become more feminine and women more masculine, to the extent that they suppressed those aspects of themselves early on. - Parker and Aldwin (1997) did find partial support for this theory, in that individuals who were more extreme in their femininity and masculinity as young adults were more likely to increase in the opposite characteristic by midlife, but men remained more masculine and women more feminine. - Although both Buhler (1968) and Loevinger (1977) were ego psychologists, they were also influenced by Jung (1933) and the humanistic movement in psychology. > Buhler emphasized meaning and goals in development rather than strict ontogenetic stages. > She defined intention as the pursuit of an objective that provides an individual with a sense of purpose in life. > Loevinger viewed development as an increase in autonomy and differentiation of self from others. * Like Jung, she felt that development involves a progressive freeing of the self from constraints due to contextual and social factors. - Maslow (1970) called this stage self-actualization, as the end point of a motivational hierarchy. > Although he is not traditionally considered a theorist in adult development, his theory is in many ways very similar to that of Loevinger and thus should be included. - In contrast, the work of Levinson (1978) was more explicitly an amalgam of Jungian and Eriksonian theories. > He posited a series of stages or life structures that are punctuated by periods of transition. - Gestalt theories also influenced theories of adult development. > Early on, Wolf- gang Kohler (1940) and the other Gestalt psychologists argued that the pattern of relationships among variables is more important than the absolute level of any particular variable. > (For example, we can recognize the tune ''Happy Birthday'' no matter which key it is in, because the meaning or import of the tune is carried in the relation- ship among the notes rather than in any particular set of notes.) > In this model, development occurs in a discontinuous series of qualitative changes. * For instance, it was the Gestalt psychologists who suggested that learning occurs via insight experiences in which new patterns of relationships among variables are established. (The standard example used is the chimpanzee's insight that two sticks can be stuck together to get down the bananas that one stick alone cannot reach.) - In many ways, this type of discontinuous development is best exemplified by Piaget's (1954) model of cognitive development. > Like Freud, though, Piaget focused primarily on childhood. - Kohlberg (1984) drew on Piaget's theory to describe a series of stages in moral development that occurred in both childhood and adulthood. - Although Loevinger's (1977) model focused on ego development and Kohlberg's on moral development, both theories described the lessening dependence on societal norms (conformism) and instead emphasized the development of autonomous reasoning capacity concerning moral issues. - Another way in which Piagetian theory influenced theories of adult development is with the notion of postformal operations. > Piaget's initial theory ended with the stage of formal operations, generally described as scientific reasoning, that most (but not all) individuals achieve in adolescence and early adulthood. - Theorists such as Pascual-Leone (1990) and Labouvie-Vief (1990) focus on more complex cognitive development in adulthood—post-formal operations, which emphasizes relativistic and dialectical reasoning. > Relativistic reasoning argues that there are very few absolutes; instead, complex thinkers understand that the context modifies decisions and thought processes, which may be carefully nuanced. Rather than an absolute such as ''lying is always wrong,'' a relativist thinker may realize that lying is wrong when one seeks to cover up wrongdoing or to harm someone but may be acceptable if one intends to prevent harm (e.g., concealing one's true feelings about someone else's new outfit). - In dialectical reasoning, it may be understood that there are often opposing but equally valid intellectual stances (thesis and counterthesis). > Rather than choosing one to be right and the other wrong, the dialectic reasoner develops ways of synthesizing contradictory information, often by recognizing that some ideas may be better applicable in some contexts than others. * For example, Newtonian and Einsteinian physics posit very different models of the universe, but one is not wrong and the other right; rather, Newtonian physics is seen as a very special and small part of Einsteinian physics, which has broader applicability. Similarly, from a dialectic view- point, there is no contradiction between religion and evolution as long as one does not take a literalist view of scriptures such as the Bible or the Koran. * Evolution can be seen as a process through which creation occurs. - Labouvie-Vief, Gru ̈ hm, and Studer (2010) also argued for the necessity of integrating emotion with cognition in adult development. > Not only do people become more cognitively complex with age but they also may become more emotionally complex. - Labouvie-Vief et al.'s (2010) study showed that cognitive and emotional complexity increases from young adulthood to midlife but then decreases in late life. Instead of emotional complexity, Pascual-Leone (1990) focused on ego transcendence, a construct that is further discussed in the following text. > Thus, the psychological adult development and aging theorists emphasized internal processes and posited that development had a goal, or telos. > That goal was variously described but usually involved psychological integration, autonomy, and/ or the development of choice in adulthood.

Psychosocial Theories of Aging: Classic Theories

1) Ontogenic models: - based in Germany - posited that developmental forces are internal and probably biologically based 2) Sociogenic schools - influenced by French sociologists such as Durkheim - argue that change in adulthood is largely due to social forces


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